蓝藻碎屑分解速率及氮磷释放形态的实验分析   总被引：19，自引：8，他引：11  

李柯  关保华  刘正文 《湖泊科学》2011,23(6):919-925

在试验条件下研究了水华蓝藻堆积使叶绿素浓度达到1600μg/L时,水体所含蓝藻形成的碎眉在水中的分解速率及其营养盐释放情况.结果表明:蓝藻碎屑的总氮含量为88.56±4.10mg/g,其在水体中有较高的分解速率,2d内即分解掉41.9％的生物量;蓝藻碎屑磷释放速率要高于氮,但其导致的水体中溶解性总氮浓度的升高则较溶解性...  相似文献   

煅烧改性净水厂污泥对底泥内源磷释放的控制效果     

李书文  周真明  杨思明  刘淑坡  李飞  苑宝玲 《湖泊科学》2019,31(4):961-968

以自主研发的煅烧改性净水厂污泥（C-WTPS）作为污染底泥活性覆盖材料,室内静态模拟实验研究C-WTPS覆盖强度对控制底泥磷释放效果的影响,分析C-WTPS和底泥中不同形态磷含量变化,探讨C-WTPS薄层覆盖对上覆水体中pH、DO和ORP的影响.结果表明,实验历时40天,在底泥TP释放强度为6.25~10.87 mg/（m²·d）时,覆盖强度为0.25、0.50、1.00、1.50和2.00 kg/m²的C-WTPS对TP平均削减率分别为59.68%、75.71%、88.75%、92.42%和96.28%,可见覆盖强度为1.00 kg/m²以上的C-WTPS能控制底泥中90%以上TP释放.C-WTPS吸附的磷主要以无机磷（IP）中的铁铝结合态磷（NAIP）形式存在,有机磷（OP）和钙磷（AP）形式较少.C-WTPS促进了底泥中易释放形态磷迁移到C-WTPS中,并转化较为稳定的形态磷,可见C-WTP覆盖不仅控制了底泥磷释放,而且也削减了底泥磷释放风险.C-WTPS覆盖后,上覆水体中pH开始呈现下降趋势,最终维持在pH=7范围波动;C-WTPS覆盖强度越大,上覆水体pH下降也明显;C-WTPS覆盖改善上覆水体中DO和ORP环境的效果不明显.  相似文献   

天津于桥水库沉积物磷赋存特征及其环境意义   总被引：2，自引：0，他引：2  

江雪  文帅龙  姚书春  郑小兰  康得军  钟继承 《湖泊科学》2018,30(3):628-639

研究天津于桥水库沉积物中磷形态的空间分布特征和垂直分布特征对了解水源型水库富营养化现状及其过程具有重要的现实意义.利用抓斗式采泥器及柱状采泥器分别采集表层沉积物样品及柱状沉积物样品,采用Psenner提出的连续提取法对沉积物磷形态进行分级测定,揭示整个水库沉积物各形态磷的空间分布特征以及不同区域垂直方向上的分布规律.结果表明:于桥水库表层沉积物总磷(TP)含量为303.7~997.8 mg/kg,各形态磷含量大小顺序依次为:钙结合态磷(Ca-P)铁结合态磷(Fe-P)残渣态磷(Res-P)铝结合态磷(Al-P)有机态磷(Org-P)可交换态磷(Ex-P).表层沉积物中Fe-P、Al-P、Ca-P与TP含量由东至西逐渐递减,主要受到黎河河水夹带的外源性磷输入的影响;Res-P含量由东至西逐渐递增,与活性磷的分布规律相反,表明水库下游比上游的水质更好.垂直分布上,南部区域底层与表层沉积物相差不大,说明从1960s以来磷的沉积量就比较大;西部区域沉积物中Fe-P和Org-P含量较高,随深度的增加有明显降低的趋势;中心区域的各形态磷和TP含量均较低,且随着深度增加逐渐降低,现阶段沉积物中的磷以滞留为主,释放潜力较小.  相似文献   

澜沧江梯级筑坝下水体氮磷分布特征及其形成机制     

李晨辉  闫兴成  丁珏  陈宇琛  林育青  陈求稳  潘保柱 《湖泊科学》2023,35(4):1320-1329

水库建设改变了河流水文情势及物质迁移转化过程,从而影响水环境质量。为探究梯级筑坝影响下河流氮、磷的空间分布特征及其形成机制,以澜沧江为研究对象,于2016年和2021年分别开展了沿程水环境监测,对比分析水体中氮、磷及其形态浓度在水库建成前后的变化及沿程分布特征,探究氮、磷变化及其沿程分布的主控因子和影响机制。结果表明：由于河流建库蓄水淹没的土地释放大量土壤有机氮,新建水库段(2021年)水体总氮(TN)浓度相比于建库前(2016年)显著上升;由于建库后水流流速减缓而促进颗粒态磷沉降,水体总磷(TP)浓度显著下降。此外,河流建库蓄水后原自然河道的水环境特征改变且利于沉积物磷的释放,筑坝后水体磷酸盐(PO₄^3--P)占生物可利用磷(Bio-P)的比例显著上升。受沿程土地利用的影响,从上游到下游水体TN浓度总体上逐渐升高,而水体TP浓度由于水库的截留效应逐渐降低。筑坝增加的水力停留时间为水库氮、磷转化提供了有利条件,主要表现为溶解性无机氮以硝态氮为主转变为以氨氮为主;同时,Bio-P中PO₄^3--P的占比...  相似文献   

环境矿物学：矿物学在环境科学研究中的应用   总被引：6，自引：0，他引：6  

徐惠芳 《高校地质学报》2000,6(2):233-244

矿物学在环境科学中的应用将是21世纪矿物学研究的一个主要方面。 作者所在实验室曾做过的一些环境矿物学研究的实例有：核废料的处置,矿物表面性质的研究,对有毒金属的还原和固定作用的微生物效应,大气烟尘微粒的研究,矿物表面阳离子的本征吸附常数之理论计算,等等。矿物-水-微生物体系在分子级别上之相互作用的定量研究,对于理解低温地球化学和生物地球化学过程将是重要的。  相似文献   

贵州红枫湖沉积物磷赋存形态及沉积历史   总被引：38，自引：4，他引：34  

王雨春  马梅  万国江  刘丛强  尹澄清 《湖泊科学》2004,16(1):22-28

采集了云贵高原深水湖泊红枫湖现代沉积物未受扰动的柱状样品,通过分析不同形态沉积磷在沉积剖面上的分布特征,并结合沉积物样品柱的210Pb、137Cs年代学研究结果,揭示了红枫湖现代沉积过程中不同形态沉积磷的早期成岩改造的时间变化序列,以及沉积磷外源输入负荷的历史变化.采用Ruttenberg法分析沉积磷的地球化学赋存形态,研究表明,红枫湖沉积物中有机磷和铁结合态磷是沉积磷的主要赋存形态,分别占沉积全磷的60%和28%.沉积磷在垂直剖面上的分布特征显示,红枫湖现代沉积过程中,沉积磷在最终埋藏前可能发生非常剧烈的形态转化和再迁移,尤其是有机磷和铁结合态磷的成岩改造可能是湖泊系统磷循环质量平衡的重要方面.年代学数据同时表明,近年的人为活动导致湖泊系统(包括沉积物)磷负荷的显著增加.  相似文献   

The determination of minor and trace element associations in coal using a sequential microwave digestion procedure     

Kay L. Laban  Brian P. Atkin 《International Journal of Coal Geology》1999,41(4):817

A sequential extraction procedure, using acid digestion in a CEM MDS-81D® microwave system, is reported for the investigation of trace and minor element associations in coal in (1) mineral phases other than pyrite, (2) pyrite and (3) the organic matrix. The concentrations of sulphate, pyrite and organic sulphur can also be determined by this method. The extract solutions from each stage are rapidly analysed by ICP-AES. The association of major, minor and trace elements with mineral and organic phases is suggested for a suite of certified reference coal samples. In stage 1, a significant percentage of the total Ba, Co, Cr, Cu, Mn, Ni, Pb and Sr was extracted suggesting an association with silicate, carbonate, sulphate and phosphate minerals for these elements. In stage 2, a proportion of the Cu, Mn, Ni, Pb and Zn was dissolved implying the occurrence of these elements in pyrite. An association with the organic matrix is suggested for Cr and also for Ba and Sr in lower rank coals.  相似文献   

Flow resistance in the coastal zone     

K. T. Houwman  L. C. Van Rijn   《Coastal Engineering》1999,38(4):313

The apparent bed roughness, the roughness value experienced by a mean flow outside the wave-boundary layer, is deduced from the physical bed roughness and the wave–current interaction mechanism. Both the physical bed roughness and the wave–current interaction are described by a (combination of) model(s). Modelling of the apparent bed roughness leads to realistic results, however, the final results are rather sensitive to the particular choice of these models. Four bed form models and two wave–current interaction models were implemented in a 1-DV flow model to calculate near-bed velocities. A comparison between measured and predicted velocities shows that reasonable results can be obtained in this way. A constant bed roughness of 0.1 m, however, leads to even better results at this site during all conditions. This can be explained by the reversed influence of the form roughness and the wave–current interaction on the apparent bed roughness value for varying wave conditions.  相似文献   

Spatial distribution of phosphorus forms in sediments in the Gulf of Gdańsk (southern Baltic Sea)     

Katarzyna Łukawska-Matuszewska  Jerzy Bolałek 《Continental Shelf Research》2008

The paper analyses the concentrations of total phosphorus and its forms in sediments from the Gulf of Gdańsk on the basis of studies conducted at 25 sampling sites in 2001–05. The phosphorus speciation analysis was performed by sequential extraction. The extensive spatial variability of P_tot concentrations and speciation was found to be dependent on the physicochemical properties of the sediments, the oxygen conditions in the water and sediments, and the depth of the water column above the sediment surface. In the coastal zone, the sedimentation of riverine suspended matter and the sorption and chemisorption processes exert a considerable influence on P speciation. Over 70% of variation of total phosphorus concentration in sediments in the Gulf of Gdańsk could be explained by changes of proportion of fine fraction of sediments (grain size <0.0625 mm). Maximum P_tot concentrations were recorded in clays and silts in the deep water, stratified part of the Gulf of Gdańsk. In the coastal zone, where sandy sediments are dominant, phosphorus concentrations were much lower; this was due to the considerable dynamics of the bottom water and intensive sea floor transport. P_tot concentrations in the Gulf of Gdańsk sediments ranged from 1.75 to 957.17 μmol g⁻¹ d.w. Of all the forms of phosphorus, the highest concentrations were found for organic phosphorus (Org-P). Of its inorganic forms, the highest concentrations were of phosphorus bound to clay minerals and aluminium oxides (NaOH-P), the lowest ones were of loosely bound phosphorus (NaCl-P). On the basis of determinations of total phosphorus concentrations in sediments of a given type and the available data on the seabed areas covered by particular sediment types in the Gulf of Gdańsk, the mass of total phosphorus in the surficial sediment layer (0–2 cm) was estimated at ca. 15.6×10³ tonnes.  相似文献   

滇池水-沉积物界面磷形态分布及潜在释放特征   总被引：14，自引：3，他引：11  

何佳  陈春瑜  邓伟明  徐晓梅  王圣瑞  刘文斌  吴雪  王丽 《湖泊科学》2015,27(5):799-810

通过现场调查和室内模拟实验,对滇池35个上覆水-沉积物磷的分布特征以及沉积物中磷释放动力学特征进行研究,结果表明:滇池表层沉积物中不同形态磷含量表现为:有机磷(OP)(1482.49±1156.82 mg/kg)钙结合态磷(Ca-P)(865.54±558.40 mg/kg)金属氧化物结合态磷(Al-P)(463.77±662.18 mg/kg)残渣态磷(Res-P)(218.52±83.11 mg/kg)可还原态磷(Fe-P)(128.13±101.56 mg/kg)弱吸附态磷(NH4Cl-P)(2.26±3.05 mg/kg);滇池上覆水草海总磷浓度处于劣Ⅳ类水平,外海不同湖区总磷浓度介于Ⅳ~Ⅴ类之间;滇池水体中的磷以颗粒态磷含量最高;滇池表层沉积物中磷的释放是由快反应和慢反应两部分组成.释放过程主要发生在前8 h内;不同区域沉积物磷的最大释放速率、最大释放量、磷的释放潜力平均值均表现为:草海外海北部外海南部湖心区;滇池表层沉积物中磷的释放主要由NH4Cl-P、Fe-P、Al-P和OP进行,其中,NH4Cl-P和Fe-P所占比重较大;磷的释放与上覆水中溶解性总磷、溶解态无机磷和溶解态有机磷呈显著正相关,预示着上覆水中磷的迁移转化更多地受到水-沉积物界面浓度梯度的控制,进一步说明不能以总磷含量来评价湖泊磷素释放的状况,需与磷形态及分布特征相结合进行分析.  相似文献